At 2:37 am on October 23, Beijing time, India took off the largest weight GSLV Mk-III launch vehicle, successfully sent 36 of the latest developments of the British One Network company, low-orbit nanocommunication satellites into the predetermined orbit. This not only means that India has begun to deploy the commercial space launch market on a large scale, but also means that the first flight of the GSLV Mk-III launch vehicle was successful and laying the foundation for India to implement manned space flight in the future.
It can be said that in the past two years, especially after the Falcon-9 launch vehicle under the United States, which has carried out the " one arrow multiple satellites " multiple times, the number of satellites that adopt this "bus collectively loaded" launch mode is increasing worldwide. But why is my country, which has outstanding aerospace strength, not keen on this aerospace launch model?
First of all, it needs to be clarified that my country is not keen on this launch mode of multiple satellites with one arrow, which is not a technical reason. On the contrary, my country is much more advanced than India and SpaceX in launching technology for multiple satellites with one arrow. For example, when my country launched the Long March 8 Yao-2 light-pole carrier rocket for the first time in February this year, it launched 22 small satellites of different types at once. Moreover, these 22 satellites were not released into a unified orbit like India and SpaceX at one time. Instead, they used adapters to send satellites into orbits of different heights. This alone directly left several streets in the airlines that India and SpaceX that would only release nano satellite in the same orbit.
In fact, my country has always been not very keen on this launch model of multiple satellites with one arrow, which is mainly directly related to my country's aerospace development plan, because my country's current aerospace development mainly focuses on continuing to carry out manned space and deep space exploration. The former is such as Shenzhou manned spacecraft, Tianzhou cargo spacecraft, and Tiangong Space Station construction, while the latter is such as Mars exploration, and lunar sampling returns. The single weight of spacecraft for manned spacecraft and deep space exploration is very large. For example, the single weight of Shenzhou manned spacecraft is nearly 9 tons, and the single weight of Tianzhou cargo spacecraft is nearly 14 tons. Whether it is Tianhe core cabin, Wentian, and Mengtian experimental cabin, the single weight of the single weight exceeds more than 20 tons.
Deep space exploration Tianwen-1 Mars rover has a single body weight of only 5 tons, but it needs to directly send it to the higher-altitude ground fire transfer orbit, which has higher requirements for the rocket's carrying capacity, thrust-to-weight ratio, and engine-based rushing; the Chang'e-5 lunar probe launched previously reached 8.2 tons, and the rocket also needs to directly send it to the Earth-Moon transfer orbit.
That alone performs large spacecraft launch missions with a weight of several tons or even dozens of tons, which has occupied the main payload of my country's space launch. For example, my country's largest Long March 5B large launch vehicle has a low-Earth orbit capacity of 22 tons, and can only launch one core compartment or experimental compartment. However, if the Long March 5B is used to perform multiple satellite launch missions with one arrow, it is estimated that the Long March 5B will be launched once, and SpaceX's Falcon-9 rocket will have to be launched at least four or five times.
However, the three fast-response launch vehicles that have been put into operation in my country in recent years are basically implementing the launch mode of multiple satellites with one arrow. For example, the Long March 6 small launch vehicle was launched in August this year with a total of 16 satellites, and the maximum launch record was 20 satellites; the Long March 11 small launch vehicle has completed a 5-star launch mission in one arrow since its first flight in 2018; the Kuaizhou-1 small launch vehicle has also completed a 6-star launch mission in one arrow since its first flight in 2013, and these three fast-response satellites mainly carry out the launch missions of some small commercial and experimental satellites.
So it is not that my country is not keen on launching multiple satellites with one arrow, but among the two major directions of my country's aerospace development, no matter which spacecraft is of great mass, it is impossible to achieve the launching mode of one arrow, one arrow, and one arrow, and other space missions are only some small commercial satellites, which require the use of multiple satellites with one arrow, which will reduce the launch cost.
If we look at the advantages of one arrow and multiple stars technology, the biggest advantage of multiple stars with one arrow is that it can make full use of the rocket's carrying capacity, improve launch efficiency, and reduce launch costs. However, this launch mode of multiple satellites with one arrow is only suitable for small nanosatellites. These satellites generally weigh only a few dozen kilograms, are very small in size, and have a short operating life, usually only one or two years.
and my country's current Long March series launch vehicle , mainly performing and breaking through to launch tasks with larger single mass and higher orbits. For example, at the end of this month, the Long March 5B launch vehicle will launch the Mengtian experimental cabin with a single weight of 22.5 tons at one time to rendezvous and dock with the Tiangong Space Station. Such a technology may not be realized even if India explores it for another 10 years, including the US SpaceX, which is very sloppy in recycling and utilizing the rockets, and it does not have this strength at the moment.
, and for this launch mode of dozens of stars with one shot, I believe that it will be carried out in no time, because my country is currently carrying out two major "state grid aerospace projects" of "Hongyan Constellation" and " Cloud Project ".
Hongyan and Xingyun Engineering are both Starlink global communication system similar to SpaceX, but the former belongs to Aerospace Science and Technology and the latter belongs to Aerospace Science and Technology . But the overall performance of both is much more advanced than Starlink. The communication satellite , which is also launched into low-Earth orbit, has a longer life, a wider signal coverage range, and a higher communication rate. It also requires a smaller number of satellites, and can adjust the satellite signal coverage rate in real time according to the population and dispersed density of the region.
In contrast, in order to reduce costs and reduce technical standards, SpaceX's "Starlink" can only reduce the performance, so it can only be used to make up the number of satellites, which has caused the entire starlink to have 20,000 to 30,000 nano-satellites. Moreover, during the construction of the starlink, some of the starlinks launched in the early stage have been retired, so it is necessary to retire and launch forever to maintain the normal operation of the entire starlink system.
Although there are rumors at this stage that Aerospace Science and Technology, Aerospace Science and Technology, China Electric Technology and several major domestic private aerospace companies have planned or are being implemented to be suspended, because low-orbit communication systems formed by small-sized nanosatellites like Starlink will cause near-Earth orbit encroachment, seriously affect satellite operation, and increase space waste. Therefore, our country has integrated these different low-orbit satellite communication systems, and the unified construction of the " State Grid System" will cover dozens of ultra-large satellite low-orbit systems covering civilian applications, including communications, health, medical care, geology, environment, meteorology, aerial photography, etc.
And as early as 2020, my country submitted a satellite system plan consisting of 12,992 satellites to International Telecommunications Union ITU. is already on the way.
